The present invention relates to imaging devices, and, more particularly, to adaptive image sensor systems and methods.
Modern electronic devices such as cellular telephones, cameras, and computers often use digital image sensors. Imagers (i.e., image sensors) often include a two-dimensional array of image sensing pixels. Each pixel typically includes a photosensor such as a photodiode that receives incident photons (light) and converts the photons into electrical signals.
In conventional imaging systems, a digital image sensor captures images of a scene at a fixed frame rate. However, it is often the case that many of the captured frames are unnecessary. Consider, as an example, an imaging system being used as a security camera in a low-traffic area. Many images captured by the imaging system will be identical (and therefore not useful) as movement in the low-traffic area is rare. However, the imaging system will still generally need to capture images at a high frame rate, to be able to adequately capture video of any events (such as a security breach) that do occur. While conventional imaging systems often reduce the frame rate of captured video in post-processing, in order to reduce the amount of storage space needed to archive the video; having the digital image sensor continually capture images at the fixed frame rate increases power consumption and results in other limitations on image sensor performance and cost.
It would therefore be desirable to be able to provide improved image sensor systems.